Class TextDetector

Content type detection of plain text documents. This detector looks at the
beginning of the document input stream and considers the document to be
a text document if no ASCII (ISO-Latin-1, UTF-8, etc.) control bytes are
found. As a special case some control bytes (up to 2% of all characters)
are also allowed in a text document if it also contains no or just a few
(less than 10%) characters above the 7-bit ASCII range.

Note that text documents with a character encoding like UTF-16 are better
detected with MagicDetector and an appropriate magic byte pattern.